| Code/Flag Figure |
Description |
Status |
|
00
|
Cloud development not observed or not observable
(Characteristic change of the state of sky during the past hour)
|
Operational
|
|
01
|
Clouds generally dissolving or becoming less developed
(Characteristic change of the state of sky during the past hour)
|
Operational
|
|
02
|
State of sky on the whole unchanged
(Characteristic change of the state of sky during the past hour)
|
Operational
|
|
03
|
Clouds generally forming or developing
(Characteristic change of the state of sky during the past hour)
|
Operational
|
|
04
|
Visibility reduced by smoke, e.g. veldt or forest fires, industrial smoke or volcanic ashes
|
Operational
|
|
05
|
Haze
|
Operational
|
|
06
|
Widespread dust in suspension in the air, not raised by wind at or near the station at the time of observation
|
Operational
|
|
07
|
Dust or sand raised by wind at or near the station at the time of observation, but no well-developed dust whirl(s) or sand whirl(s), and no duststorm or sandstorm seen; or, in the case of sea stations and coastal stations, blowing spray at the station
|
Operational
|
|
08
|
Well-developed dust whirl(s) or sand whirl(s) seen at or near the station during the preceding hour or at the same time of observation, but no duststorm or sandstorm
|
Operational
|
|
09
|
Duststorm or sandstorm within sight at the time of observation, or at the station during the preceding hour
|
Operational
|
|
10
|
Mist
|
Operational
|
|
11
|
Patches
(shallow fog or ice fog at the station, whether on land or sea, not deeper than about 2 metres on land or 10 metres at sea)
|
Operational
|
|
12
|
More or less continuous
(shallow fog or ice fog at the station, whether on land or sea, not deeper than about 2 metres on land or 10 metres at sea)
|
Operational
|
|
13
|
Lightning visible, no thunder heard
|
Operational
|
|
14
|
Precipitation within sight, not reaching the ground or the surface of the sea
|
Operational
|
|
15
|
Precipitation within sight, reaching the ground or the surface of the sea, but distant, i.e. estimated to be more than 5 km from the station
|
Operational
|
|
16
|
Precipitation within sight, reaching the ground or the surface of the sea, near to, but not at the station
|
Operational
|
|
17
|
Thunderstorm, but no precipitation at the time of observation
|
Operational
|
|
18
|
Squalls
(at or within sight of the station during the preceding hour or at the time of observation)
|
Operational
|
|
19
|
Funnel cloud(s)
(at or within sight of the station during the preceding hour or at the time of observation)
|
Operational
|
|
20
|
Drizzle (not freezing) or snow grains
(not falling as shower(s))
|
Operational
|
|
21
|
Rain (not freezing)
(not falling as shower(s))
|
Operational
|
|
22
|
Snow
(not falling as shower(s))
|
Operational
|
|
23
|
Rain and snow or ice pellets
(not falling as shower(s))
|
Operational
|
|
24
|
Freezing drizzle or freezing rain
(not falling as shower(s))
|
Operational
|
|
25
|
Shower(s) of rain
(not falling as shower(s))
|
Operational
|
|
26
|
Shower(s) of snow, or of rain and snow
|
Operational
|
|
27
|
Shower(s) of hail, or of rain and hail
|
Operational
|
|
28
|
Fog or ice fog
|
Operational
|
|
29
|
Thunderstorm (with or without precipitation)
|
Operational
|
|
30
|
Slight or moderate duststorm or sandstorm
(has decreased during the preceding hour)
|
Operational
|
|
31
|
Slight or moderate duststorm or sandstorm
(no appreciable change during the preceding hour)
|
Operational
|
|
32
|
Slight or moderate duststorm or sandstorm
(has begun or has increased during the preceding hour)
|
Operational
|
|
33
|
Severe duststorm or sandstorm
(has decreased during the preceding hour)
|
Operational
|
|
34
|
Severe duststorm or sandstorm
(no appreciable change during the preceding hour)
|
Operational
|
|
35
|
Severe duststorm or sandstorm
(has begun or has increased during the preceding hour)
|
Operational
|
|
36
|
Slight or moderate drifting snow
(generally low (below eye level))
|
Operational
|
|
37
|
Heavy drifting snow
(generally low (below eye level))
|
Operational
|
|
38
|
Slight or moderate blowing snow
(generally high (above eye level))
|
Operational
|
|
39
|
Heavy blowing snow
(generally high (above eye level))
|
Operational
|
|
40
|
Fog or ice fog at a distance at the time of observation, but not at the station during the preceding hour, the fog or ice fog extending to a level above that of the observer
|
Operational
|
|
41
|
Fog or ice fog in patches
|
Operational
|
|
42
|
Fog or ice fog, sky visible
(has become thinner during the preceding hour)
|
Operational
|
|
43
|
Fog or ice fog, sky invisible
(has become thinner during the preceding hour)
|
Operational
|
|
44
|
Fog or ice fog, sky visible
(no appreciable change during the preceding hour)
|
Operational
|
|
45
|
Fog or ice fog, sky invisible
(no appreciable change during the preceding hour)
|
Operational
|
|
46
|
Fog or ice fog, sky visible
(has begun or has become thicker during the preceding hour)
|
Operational
|
|
47
|
Fog or ice fog, sky invisible
(has begun or has become thicker during the preceding hour)
|
Operational
|
|
48
|
Fog, depositing rime, sky visible
|
Operational
|
|
49
|
Fog, depositing rime, sky invisible
|
Operational
|
|
50
|
Drizzle, not freezing, intermittent
(slight at time of observation)
|
Operational
|
|
51
|
Drizzle, not freezing, continuous
(slight at time of observation)
|
Operational
|
|
52
|
Drizzle, not freezing, intermittent
(moderate at time of observation)
|
Operational
|
|
53
|
Drizzle, not freezing, continuous
(moderate at time of observation)
|
Operational
|
|
54
|
Drizzle, not freezing, intermittent
(heavy (dense) at time of observation)
|
Operational
|
|
55
|
Drizzle, not freezing, continuous
(heavy (dense) at time of observation)
|
Operational
|
|
56
|
Drizzle, freezing, slight
|
Operational
|
|
57
|
Drizzle, freezing, moderate or heavy (dense)
|
Operational
|
|
58
|
Drizzle and rain, slight
|
Operational
|
|
59
|
Drizzle and rain, moderate or heavy
|
Operational
|
|
60
|
Rain, not freezing, intermittent
(slight at time of observation)
|
Operational
|
|
61
|
Rain, not freezing, continuous
(slight at time of observation)
|
Operational
|
|
62
|
Rain, not freezing, intermittent
(moderate at time of observation)
|
Operational
|
|
63
|
Rain, not freezing, continuous
(moderate at time of observation)
|
Operational
|
|
64
|
Rain, not freezing, intermittent
(heavy at time of observation)
|
Operational
|
|
65
|
Rain, not freezing, continuous
(heavy at time of observation)
|
Operational
|
|
66
|
Rain, freezing, slight
|
Operational
|
|
67
|
Rain, freezing, moderate or heavy
|
Operational
|
|
68
|
Rain or drizzle and snow, slight
|
Operational
|
|
69
|
Rain or drizzle and snow, moderate or heavy
|
Operational
|
|
70
|
Intermittent fall of snowflakes
(slight at time of observation)
|
Operational
|
|
71
|
Continuous fall of snowflakes
(slight at time of observation)
|
Operational
|
|
72
|
Intermittent fall of snowflakes
(moderate at time of observation)
|
Operational
|
|
73
|
Continuous fall of snowflakes
(moderate at time of observation)
|
Operational
|
|
74
|
Intermittent fall of snowflakes
(heavy at time of observation)
|
Operational
|
|
75
|
Continuous fall of snowflakes
(heavy at time of observation)
|
Operational
|
|
76
|
Diamond dust (with or without fog)
|
Operational
|
|
77
|
Snow grains (with or without fog)
|
Operational
|
|
78
|
Isolated star-like snow crystals (with or without fog)
|
Operational
|
|
79
|
Ice pellets
|
Operational
|
|
80
|
Rain shower(s), slight
|
Operational
|
|
81
|
Rain shower(s), moderate or heavy
|
Operational
|
|
82
|
Rain shower(s), violent
|
Operational
|
|
83
|
Shower(s) of rain and snow mixed, slight
|
Operational
|
|
84
|
Shower(s) of rain and snow mixed, moderate or heavy
|
Operational
|
|
85
|
Snow shower(s), slight
|
Operational
|
|
86
|
Snow shower(s), moderate or heavy
|
Operational
|
|
87
|
Shower(s) of snow pellets or small hail, with or without rain or rain and snow mixed
(slight)
|
Operational
|
|
88
|
Shower(s) of snow pellets or small hail, with or without rain or rain and snow mixed
(moderate or heavy)
|
Operational
|
|
89
|
Shower(s) of hail, with or without rain or rain and snow mixed, not associated with thunder
(slight)
|
Operational
|
|
90
|
Shower(s) of hail, with or without rain or rain and snow mixed, not associated with thunder
(moderate or heavy)
|
Operational
|
|
91
|
Slight rain at time of observation
(Thunderstorm during the preceding hour but not at time of observation)
|
Operational
|
|
92
|
Moderate or heavy rain at time of observation
(Thunderstorm during the preceding hour but not at time of observation)
|
Operational
|
|
93
|
Slight snow, or rain and snow mixed or hail at time of observation
(Thunderstorm during the preceding hour but not at time of observation)
|
Operational
|
|
94
|
Moderate or heavy snow, or rain and snow mixed or hail at time of observation
(Thunderstorm during the preceding hour but not at time of observation)
|
Operational
|
|
95
|
Thunderstorm, slight or moderate, without hail, but with rain and/or snow at time of observation
(Thunderstorm at time of observation)
|
Operational
|
|
96
|
Thunderstorm, slight or moderate, with hail at time of observation
(Thunderstorm at time of observation)
|
Operational
|
|
97
|
Thunderstorm, heavy, without hail, but with rain and/or snow at time of observation
(Thunderstorm at time of observation)
|
Operational
|
|
98
|
Thunderstorm combined with duststorm or sandstorm at time of observation
(Thunderstorm at time of observation)
|
Operational
|
|
99
|
Thunderstorm, heavy, with hail at time of observation
(Thunderstorm at time of observation)
|
Operational
|
|
100
|
No significant weather observed
|
Operational
|
|
101
|
Clouds generally dissolving or becoming less developed during the past hour
|
Operational
|
|
102
|
State of sky on the whole unchanged during the past hour
|
Operational
|
|
103
|
Clouds generally forming or developing during the past hour
|
Operational
|
|
104
|
Haze or smoke, or dust in suspension in the air, visibility equal to, or greater than, 1 km
|
Operational
|
|
105
|
Haze or smoke, or dust in suspension in the air, visibility less than 1 km
|
Operational
|
|
106-109
|
Reserved
|
Operational
|
|
110
|
Mist
|
Operational
|
|
111
|
Diamond dust
|
Operational
|
|
112
|
Distant lightning
|
Operational
|
|
113-117
|
Reserved
|
Operational
|
|
118
|
Squalls
|
Operational
|
|
119
|
Reserved
|
Operational
|
|
120
|
Fog
|
Operational
|
|
121
|
PRECIPITATION
|
Operational
|
|
122
|
Drizzle (not freezing) or snow grains
|
Operational
|
|
123
|
Rain (not freezing)
|
Operational
|
|
124
|
Snow
|
Operational
|
|
125
|
Freezing drizzle or freezing rain
|
Operational
|
|
126
|
Thunderstorm (with or without precipitation)
|
Operational
|
|
127
|
BLOWING OR DRIFTING SNOW OR SAND
|
Operational
|
|
128
|
Blowing or drifting snow or sand, visibility equal to, or greater than, 1 km
|
Operational
|
|
129
|
Blowing or drifting snow or sand, visibility less than 1 km
|
Operational
|
|
130
|
FOG
|
Operational
|
|
131
|
Fog or ice fog in patches
|
Operational
|
|
132
|
Fog or ice fog, has become thinner during the past hour
|
Operational
|
|
133
|
Fog or ice fog, no appreciable change during the past hour
|
Operational
|
|
134
|
Fog or ice fog, has begun or become thicker during the past hour
|
Operational
|
|
135
|
Fog, depositing rime
|
Operational
|
|
136-139
|
Reserved
|
Operational
|
|
140
|
PRECIPITATION
|
Operational
|
|
141
|
Precipitation, slight or moderate
|
Operational
|
|
142
|
Precipitation, heavy
|
Operational
|
|
143
|
Liquid precipitation, slight or moderate
|
Operational
|
|
144
|
Liquid precipitation, heavy
|
Operational
|
|
145
|
Solid precipitation, slight or moderate
|
Operational
|
|
146
|
Solid precipitation, heavy
|
Operational
|
|
147
|
Freezing precipitation, slight or moderate
|
Operational
|
|
148
|
Freezing precipitation, heavy
|
Operational
|
|
149
|
Reserved
|
Operational
|
|
150
|
DRIZZLE
|
Operational
|
|
151
|
Drizzle, not freezing, slight
|
Operational
|
|
152
|
Drizzle, not freezing, moderate
|
Operational
|
|
153
|
Drizzle, not freezing, heavy
|
Operational
|
|
154
|
Drizzle, freezing, slight
|
Operational
|
|
155
|
Drizzle, freezing, moderate
|
Operational
|
|
156
|
Drizzle, freezing, heavy
|
Operational
|
|
157
|
Drizzle and rain, slight
|
Operational
|
|
158
|
Drizzle and rain, moderate or heavy
|
Operational
|
|
159
|
Reserved
|
Operational
|
|
160
|
RAIN
|
Operational
|
|
161
|
Rain, not freezing, slight
|
Operational
|
|
162
|
Rain, not freezing, moderate
|
Operational
|
|
163
|
Rain, not freezing, heavy
|
Operational
|
|
164
|
Rain, freezing, slight
|
Operational
|
|
165
|
Rain, freezing, moderate
|
Operational
|
|
166
|
Rain, freezing, heavy
|
Operational
|
|
167
|
Rain (or drizzle) and snow, slight
|
Operational
|
|
168
|
Rain (or drizzle) and snow, moderate or heavy
|
Operational
|
|
169
|
Reserved
|
Operational
|
|
170
|
SNOW
|
Operational
|
|
171
|
Snow, slight
|
Operational
|
|
172
|
Snow, moderate
|
Operational
|
|
173
|
Snow, heavy
|
Operational
|
|
174
|
Ice pellets, slight
|
Operational
|
|
175
|
Ice pellets, moderate
|
Operational
|
|
176
|
Ice pellets, heavy
|
Operational
|
|
177
|
Snow grains
|
Operational
|
|
178
|
Ice crystals
|
Operational
|
|
179
|
Reserved
|
Operational
|
|
180
|
SHOWER(S) OR INTERMITTENT PRECIPITATION
|
Operational
|
|
181
|
Rain shower(s) or intermittent rain, slight
|
Operational
|
|
182
|
Rain shower(s) or intermittent rain, moderate
|
Operational
|
|
183
|
Rain shower(s) or intermittent rain, heavy
|
Operational
|
|
184
|
Rain shower(s) or intermittent rain, violent
|
Operational
|
|
185
|
Snow shower(s) or intermittent snow, slight
|
Operational
|
|
186
|
Snow shower(s) or intermittent snow, moderate
|
Operational
|
|
187
|
Snow shower(s) or intermittent snow, heavy
|
Operational
|
|
188
|
Reserved
|
Operational
|
|
189
|
Hail
|
Operational
|
|
190
|
THUNDERSTORM
|
Operational
|
|
191
|
Thunderstorm, slight or moderate, with no precipitation
|
Operational
|
|
192
|
Thunderstorm, slight or moderate, with rain showers and/or snow showers
|
Operational
|
|
193
|
Thunderstorm, slight or moderate, with hail
|
Operational
|
|
194
|
Thunderstorm, heavy, with no precipitation
|
Operational
|
|
195
|
Thunderstorm, heavy, with rain showers and/or snow showers
|
Operational
|
|
196
|
Thunderstorm, heavy, with hail
|
Operational
|
|
197-198
|
Reserved
|
Operational
|
|
199
|
Tornado
|
Operational
|
|
200-203
|
Not used
|
Operational
|
|
204
|
Volcanic ash suspended in the air aloft
|
Operational
|
|
205
|
Not used
|
Operational
|
|
206
|
Thick dust haze, visibility less than 1 km
|
Operational
|
|
207
|
Blowing spray at the station
|
Operational
|
|
208
|
Drifting dust (sand)
|
Operational
|
|
209
|
Wall of dust or sand in distance (like haboob)
|
Operational
|
|
210
|
Snow haze
|
Operational
|
|
211
|
Whiteout
|
Operational
|
|
212
|
Not used
|
Operational
|
|
213
|
Lightning, cloud to surface
|
Operational
|
|
214-216
|
Not used
|
Operational
|
|
217
|
Dry thunderstorm
|
Operational
|
|
218
|
Not used
|
Operational
|
|
219
|
Tornado cloud (destructive) at or within sight of the station during preceding hour or at the time of observation
|
Operational
|
|
220
|
Deposition of volcanic ash
|
Operational
|
|
221
|
Deposition of dust or sand
|
Operational
|
|
222
|
Deposition of dew
|
Operational
|
|
223
|
Deposition of wet snow
|
Operational
|
|
224
|
Deposition of soft rime
|
Operational
|
|
225
|
Deposition of hard rime
|
Operational
|
|
226
|
Deposition of hoar frost
|
Operational
|
|
227
|
Deposition of glaze
|
Operational
|
|
228
|
Deposition of ice crust (ice slick)
|
Operational
|
|
229
|
Not used
|
Operational
|
|
230
|
Duststorm or sandstorm with temperature below 0 °C
|
Operational
|
|
231-238
|
Not used
|
Operational
|
|
239
|
Blowing snow, impossible to determine whether snow is falling or not
|
Operational
|
|
240
|
Not used
|
Operational
|
|
241
|
Fog on sea
|
Operational
|
|
242
|
Fog in valleys
|
Operational
|
|
243
|
Arctic or Antarctic sea smoke
|
Operational
|
|
244
|
Steam fog (sea, lake or river)
|
Operational
|
|
245
|
Steam log (land)
|
Operational
|
|
246
|
Fog over ice or snow cover
|
Operational
|
|
247
|
Dense fog, visibility 60-90 m
|
Operational
|
|
248
|
Dense fog, visibility 30-60 m
|
Operational
|
|
249
|
Dense fog, visibility less than 30 m
|
Operational
|
|
250
|
Drizzle, rate of fall - less than 0.10 mm h-1
|
Operational
|
|
251
|
Drizzle, rate of fall - 0.10-0.19 mm h-1
|
Operational
|
|
252
|
Drizzle, rate of fall - 0.20-0.39 mm h-1
|
Operational
|
|
253
|
Drizzle, rate of fall - 0.40-0.79 mm h-1
|
Operational
|
|
254
|
Drizzle, rate of fall - 0.80-1.59 mm h-1
|
Operational
|
|
255
|
Drizzle, rate of fall - 1.60-3.19 mm h-1
|
Operational
|
|
256
|
Drizzle, rate of fall - 3.20-6.39 mm h-1
|
Operational
|
|
257
|
Drizzle, rate of fall - 6.4 mm h-1 or more
|
Operational
|
|
258
|
Not used
|
Operational
|
|
259
|
Drizzle and snow
|
Operational
|
|
260
|
Rain, rate of fall - less than 1.0 mm h-1
|
Operational
|
|
261
|
Rain, rate of fall - 1.0-1.9 mm h-1
|
Operational
|
|
262
|
Rain, rate of fall - 2.0-3.9 mm h-1
|
Operational
|
|
263
|
Rain, rate of fall - 4.0-7.9 mm h-1
|
Operational
|
|
264
|
Rain, rate of fall - 8.0-15.9 mm h-1
|
Operational
|
|
265
|
Rain, rate of fall - 16.0-31.9 mm h-1
|
Operational
|
|
266
|
Rain, rate of fall - 32.0-63.9 mm h-1
|
Operational
|
|
267
|
Rain, rate of fall - 64.0 mm h-1 or more
|
Operational
|
|
268-269
|
Not used
|
Operational
|
|
270
|
Snow, rate of fall - less than 1.0 cm h-1
|
Operational
|
|
271
|
Snow, rate of fall - 1.0-1.9 cm h-1
|
Operational
|
|
272
|
Snow, rate of fall - 2.0-3.9 cm h-1
|
Operational
|
|
273
|
Snow, rate of fall - 4.0-7.9 cm h-1
|
Operational
|
|
274
|
Snow, rate of fall - 8.0-15.9 cm h-1
|
Operational
|
|
275
|
Snow, rate of fall - 16.0-31.9 cm h-1
|
Operational
|
|
276
|
Snow, rate of fall - 32.0-63.9 cm h-1
|
Operational
|
|
277
|
Snow, rate of fall - 64.0 cm h-1 or more
|
Operational
|
|
278
|
Snow or ice crystal precipitation from a clear sky
|
Operational
|
|
279
|
Wet snow, freezing on contact
|
Operational
|
|
280
|
Precipitation of rain
|
Operational
|
|
281
|
Precipitation of rain, freezing
|
Operational
|
|
282
|
Precipitation of rain and snow mixed
|
Operational
|
|
283
|
Precipitation of snow
|
Operational
|
|
284
|
Precipitation of snow pellets or small hall
|
Operational
|
|
285
|
Precipitation of snow pellets or small hail, with rain
|
Operational
|
|
286
|
Precipitation of snow pellets or small hail, with rain and snow mixed
|
Operational
|
|
287
|
Precipitation of snow pellets or small hail, with snow
|
Operational
|
|
288
|
Precipitation of hail
|
Operational
|
|
289
|
Precipitation of hail, with rain
|
Operational
|
|
290
|
Precipitation of hall, with rain and snow mixed
|
Operational
|
|
291
|
Precipitation of hail, with snow
|
Operational
|
|
292
|
Shower(s) or thunderstorm over sea
|
Operational
|
|
293
|
Shower(s) or thunderstorm over mountains
|
Operational
|
|
294-299
|
Not used
|
Operational
|
|
300-507
|
Reserved
|
Operational
|
|
508
|
No significant phenomenon to report, present and past weather omitted
|
Operational
|
|
509
|
No observation, data not available, present and past weather omitted
|
Operational
|
|
510
|
Present and past weather missing, but expected
|
Operational
|
|
511
|
Missing value
|
Operational
|